Night of the Triffids
by theflashisgone
Summary: Strange spores sprout in the hub.


Torchwood/Day of the Triffids x-over

_Author's note: An SCBA is a Self-Contained Breathing Apparatus, used as a means of providing the wearers of hazmat suits with air. Also, flamethrowers are generally fuelled by napalm, which is actually rather difficult to ignite, but let's pretend for the sake of the story that flamethrowers are fuelled by something less horrible for the immediate environment and napalm ignites like hydrogen gas._

Ianto was the first person to notice anything odd, although he didn't realize it at the time. While walking down a hallway in the lower levels, he came to an intersection with the stairs to the tunnels and found the floor and walls coated with an oddly fibrous dust. Assuming it to be asbestos from the ancient insulation that many of the rooms down there still had, he quickly donned a mask and cleaned it up. Later, they speculated that some of it got onto his clothes and hitched a ride to the hothouse, where it ended up in the plant pots and compost bin.

There, the bits of dust proved that they were actually seeds by germinating and taking root. Owen took notice when he realized that virtually every pot was suddenly growing what looked a bit like umbrella papyrus, but with wavy, purplish leaves. Even the compost and the open bags of potting soil had the little plants in them. Suspecting that the plants' sudden appearance out of nowhere was a bad thing, he notified the rest of the team. Together, they collected every one of the plants they could find and repotted them in trays, which Owen placed in different light and soil conditions to see how hardy they were and what their optimal conditions were. In all, there were over fifty of the little plantlets.

Several weeks passed, and the plants grew larger. The smallest ones in each tray had died, leaving a total of about fifteen plants that were moved to pots to accommodate their growth. Even the ones that Owen had deprived of light were almost two feet tall, while those provided with the most light were well over three feet in height. The purplish clusters of leaves had gotten bigger and more ferny in appearance, and greener in the plants that had more light, while the base of the stem had swollen, suggesting the top of a tuberous root. Above the leaves, a stem poked up, terminating in a pointy bud. Midway between the leaves and the developing flower, three branches poked a couple inches out of the stem before bending ninety degrees to point up, parallel to the stem itself. Prodding at the plants, Gwen discovered that while the vertical part of each branch was fairly stiff, the bendy part was flexible enough that the vertical part could rap against the stem, producing a tapping sound.

When the buds started opening to reveal orange jack-in-the-pulpit-like flowers, Owen began to worry, as they reminded him of the monsters of a classic sci-fi novel, but he didn't voice his fears to the rest of the team. His job exposed him to strange things, but that didn't remove science fiction from the category of fiction. When he came in one day to find two of the now six-foot-tall plants out of their pots, standing in the middle of the floor on three stumpy legs, Owen froze for a moment. He saw movement in his peripheral vision and ducked to the side just fast enough to dodge the stinger one of them shot at him, before he bolted out of the hothouse, slamming the door behind him.

"Tosh! Put the hub in lockdown; make sure none of the air from in here vents outside. We've got a problem!" Owen shouted.

Jack came down the stairs as the main lights turned off, to be replaced by emergency lighting. "Owen, what's up? It better be pretty serious if we're unable to leave or get fresh air for the next few hours."

"Actually," Tosh announced, "I managed to set it up so fresh air can still circulate, but all outgoing air will be filtered for anything larger than 200 microns."

"And anyway," Ianto added, "including the lower levels, most of which shouldn't be sealed off by a lockdown, the hub contains enough air to last us a bit more than three years. Assuming, of course, that we don't all decide to train for a marathon in that time."

Owen had opened his mouth to explain what the emergency was, but at Ianto's comment, he stopped. "How the _hell_ do you know how long the air would last us?" He demanded.

"I know everything," Ianto replied smugly. "Also, it says how much air the hub holds in the lockdown protocol forms. If the average person uses 550 litres of oxygen each day while at rest, and there are five of us, plus Janet and Myfanwy, whose metabolism is about four times that of a human, it works out to about three years. A bit more if you take the plants in the hothouse into account, a bit less if you account for anything else in the cells and the fact that we're not really at rest."

"Huh. Can you send me all that sort of info that you have? That'd be a good thing for me to have handy in case of airborne contaminants."

"Owen," Jack interrupted, "as impressive as Ianto's knowledge of the hub is, perhaps you should tell us why you initiated a lockdown?"

"Oh, right! You know those plants that sprouted a few weeks ago? Well, I figured out what they are. We do _not_ want those things sprouting outside of the hub."

"Well, what are they, Owen?" Gwen asked.

"Are any of you familiar with _The Day of the Triffids_? Book by John Wyndham?"

Jack, Gwen, and Tosh shook their heads.

"Owen," Ianto reasoned, "I agree that those things bear a disturbing resemblance to them, but triffids are fictitious."

"Yeah, that's what I thought until I went in just now and saw a couple of them standing on the floor!"

Ianto opened his mouth to reply in an alarmed manner, judging by his expression.

"Wait. Guys, what are triffids?" Jack blurted.

"They're plants that can walk and hunt and eat things, and if any of them sprout outside, they could take over."

"Owen, the fact that something resembling a fictional monster has turned doesn't mean that's what they are," Tosh pointed out.

"Look, they look almost exactly as they were described in the book, and one of them already tried to kill me. I'd say they're bloody close enough!"

"Okay, so Owen's established that they're dangerous," Jack interjected. "Whatever they are, we're right on the rift, so that's probably where they came from. Maybe the author was a Torchwood operative who wrote under a pseudonym or something. Anyway, they're still plants, right? So they can't see to hunt, they have to just wait for prey to come to them. We can just keep them in the hothouse. So, Owen, why the lockdown?"

"Jack," Ianto explained, "they may not be able to see, but according to the book, they have quite accurate hearing. They find you by sound and lash out at you with a venomous stinger that's stored in the flower."

"And," Owen added, "each one can produce hundreds of tiny, airborne seeds. I don't know how to tell when they're mature enough to produce seeds, which is why we need the ventilation turned off."

"Okay. Well, they still don't have hands to open a door with, so they're stuck in the hothouse for now. Team meeting in five, and you two can tell us everything you can remember about these things from the book." Jack dismissed them to get anything they might need and headed for the boardroom.

They had finished with Ianto and Owen's somewhat unorthodox briefing and were now drawing up a plan of action. Neither of them had read the book since secondary school, and Ianto had actually lost the book and never finished it, but between them they managed to outline the plot fairly accurately.

"Okay, they can't kill me, so I'll go in with a flamethrower and set fire to them," Jack proposed enthusiastically. He had liked the idea of torching them the minute Owen mentioned that part of the book.

"And set fire to all the other plants, and possibly the entire hub? Jack, that's a terrible idea," Gwen argued. Jack tried to defend his idea, but backed down when Ianto and Owen threatened to gang up on him and lock him in the cells if he tried it. They didn't often get along in the others' presence, but the prospect of Owen's plants being destroyed and the hub being made a complete mess convinced them to put aside their differences for the time being.

"Fine," Jack finally grumbled, "what do you propose?"

"Well," Tosh said, "I think cutting the dangerous part off makes the most sense. You can go in with a pair of hedge trimmers and cut the stems off, then we can move them someplace where we _can_ burn them safely."

"Do we even have hedge trimmers?" Gwen asked.

Everyone turned to Ianto. "I don't believe we have hedge trimmers, but there's a large pair of bolt cutters in the 'S' section in the locked part of the archives."

"The 'S' section of the locked part?"

"'S' for 'shears' and locked because it's a potentially destructive tool and Jack doesn't have the key."

"Hey!" Jack protested, "I'm not _that_ untrustworthy."

"This from the man who almost lost a suspect because she shouted 'Look! A distraction!'"

Jack had the decency to look sheepish.

"Right," Ianto continued, "I'll go fetch those so we can get to work destroying the triffids. Jack, we have some body armour in the bottom drawers on the left in the armoury. See if any of it fits you. Less dying is probably a good thing."

Ianto found the bolt cutters with no trouble, as well as some herbicidal sprays and ski goggles, as he had remembered that the narrator of the book had been nearly blinded by getting triffid venom in his eyes. He headed back to the main hub and was in the same corridor where he had picked up the seeds to begin with when he suddenly heard a rattling noise coming from behind him. He spun around to look for the source, but there was only the empty hallway behind him, intersecting with the hallway he had just come out of. He silently pulled out a torch and moved to the other side of the hallway to look through the door he'd just come through.

As he moved, he felt something whoosh past his head, and turned in time to see the triffid that had snuck up on him retracting its stinger for another try. He darted though the door to the other hallway and slammed the door, locking it. Looking through the reinforced window, he could see the triffid rapping its sticks against its stem to produce the rattling he had heard. Another joined it, and Ianto reached for his comm to call for help.

"Tosh, help!" he whispered, worried that the plants would hear him.

She quickly responded. "Ianto, what's wrong?"

"Have any of the triffids in the hothouse gotten out?"

He heard her typing, presumably to bring up the CCTV. "No, although they've started to make a rattling noise. Why do you ask?"

"There are at least two down here. One of them almost hit me with its stinger, and now they've got me trapped in this subsection. I think they might be communicating with each other. These ones are rattling, too."

Jack joined the conversation. "Where exactly are you?"

"Level five, section IV, in the hallway leading to the locked area and the filing office."

"Is there anything flammable in the hallway where the triffids are?"

Ianto checked out the window. The hallway itself was empty except for the plants, and the nearest storage rooms were down a ways and behind fireproof doors. "No. Go ahead and torch them."

"Yes!" Jack cheered.

"Jack!" Tosh scolded, "Ianto's in danger!"

"I know, but I get to come to his rescue literally in a blaze of glory. Ianto, we'll be down soon. Let us know if anything changes."

"Alright," Jack called to the group in the main hub, "Ianto's stranded in the archives and there may be any number of triffids down there with him. I'm going to try and collect the top of one of the triffids in the hothouse and Owen, I want you to see if you can figure out what type of toxin it uses and if any of the antivenins we have could be effective for treating it. Gwen, you and I will go down there with mid-range flamethrowers and get Ianto out. Tosh, once we're on level five, we'll need you to direct us to where Ianto is, and make sure he can talk to us and knows we're coming. Any questions? No? Alright, let's go!"

Jack grabbed a knife from the kitchen and crept into the hothouse, where he proceeded to hack off the flower of the nearest triffid. Unfortunately, one of the others stung him on his way out, and he just managed to get out with his prize and close the remaining triffids in before succumbing to the venom. Owen and Gwen carried him down to the autopsy bay, where Owen took several blood samples to see how the toxin it used affected the blood. He then hooked Jack up to an EKG just in time to monitor his return to life.

And the heart attack that promptly followed.

Three resurrections, several charges of the defibrillator, and almost forty-five minutes later, Jack got shakily to his feet and gathered Gwen and the flamethrowers to go rescue Ianto, who Tosh had kept up to speed on Jack's progress. They left Owen working on samples of the venom and headed down to the lower levels.

"Tosh, how are we doing?"

"Turn right at the end of the hallway, but be careful. That's the hallway where Ianto's two triffids are. After that, there should be some stairs on the left and a door about five metres down the right side, with another door four metres past that on the left. Ianto's behind the door on the right."

Jack and Gwen edged around the corner to see a group of seven triffids clustered around a door on the right. They opened fire and advanced on the plants, pursuing the ones that tried to escape down the hallway. Once the triffids had been reduced to charred stumps, the door unlocked and Ianto came out. He put his hands on his hips and glared at Jack.

"What? Doesn't the hero at least get a 'thank you' from his damsel-in-distress?"

"First, Jack, I am not a damsel in any sense of the word. Second, you said you would be right down, which you would have been if, third, you had made even the slightest effort to keep yourself from dying!" Ianto snapped.

"Ianto, there's only so fast even I can cut through an inch of wood with a kitchen knife. It's not my fault those plants move faster than that! If you had gotten hurt by those things, Owen would need a sample of the venom in order to treat it."

"Were you even listening when I told you to wear body armour? Tosh told me you got hit in the back, and if Kevlar can stop a bullet, it would sure as hell have stopped that plant—if, that is, you were actually wearing it."

"Ianto–"

"Guys?" Gwen interrupted their argument, "Look."

They turned to look where she was pointing and saw a dozen or so triffids standing in the hallway they needed to go back up, with more coming from the stairs that led to the tunnels. Jack swore and shooed Gwen and Ianto back into the hallway Ianto had been holed up in, following them in and locking the door. They watched the triffids crowd around the door, pushing on it and trying to break through it.

"Tosh?" Jack called. "We have a problem. Those things must have come from the tunnels, because there's a tonne of them coming up. I think we can chase them back down with the flamethrowers, but we need a plan to deal with them, as well as flushing out any more that might be wandering around the archives. Any thoughts?"

"Well," Tosh suggested, "if you can get them down to the tunnels, you could napalm them. We'd have to seal off the area to prevent oxygen loss from the hub, and then deal with the resulting pollutants in the tunnels, but it would be a pretty efficient way to burn them all. After that, I can use heat detection to find any other triffids. Plants generate some heat as a byproduct of cellular respiration, so if I filter out heat above a certain level, the brightest heat signatures should be the triffids."

"Tosh, you're wonderful," Ianto told her. "Remind me to make you some of the Jamaican Blue Mountain coffee when this is over."

"What about me?" Jack grumbled.

"Jack, you do something exceptionally brilliant and I'll make you some of the expensive stuff, too. First, though, let's get out of this hallway."

"Right. Ianto, you're not armed, so you stay here while Gwen and I chase these things into the tunnels."

Ianto wasn't happy about staying put, but he didn't voice any objections while Jack opened the door just enough to stick the nozzle of the flamethrower through, and set fire to the nearest triffids. When the plants backed off enough for them to get out, he and Gwen attacked the mob in the hallway, flamethrowers blazing. The triffids retreated, some going back down the stairs and others going further up the hallway, towards the stairs to the other levels. Gwen stayed to hold the stairs while Jack torched the ones that tried to escape.

Jack came back to where Gwen was and Ianto emerged from where he had been hiding, still holding the herbicide, bolt cutters, and ski goggles. They agreed that Jack would make sure none of the triffids came back up from the tunnels, while Gwen and Ianto went to get napalm, a third flamethrower, and more flamethrower fuel, as well as oxygen tanks, hazmat suits, headlamps and a temporary sealable door to keep the chemicals from the napalm from filling up the hub. They returned, carrying everything with a pallet truck.

After they donned the hazmat suits and turned on their SCBAs, Ianto sealed the top of the stairs before following Gwen and Jack down to the tunnels, spraying the triffids they found with napalm. Ianto, having the best knowledge of the labyrinthine tunnel system, made sure they flushed the triffids out of all the nooks and crannies, while Tosh used heat sensing to locate the hard-to-find ones. Eventually, they came across a large, muddy tunnel that had once been part of the storm sewers. There, they found hundreds of triffids of various ages, all somehow flourishing in the darkness.

"Well," Ianto said, "I guess we know how they got into the hub."

"How do you mean?" Gwen asked.

"I cleaned up what I thought was asbestos dust from the top of the stairs a month or two back. See this fuzzy stuff coating the top of the mud?" He pointed. "That's what it looked like. It must be their seeds."

"So how did those seeds get from the stairs to the hothouse?" Jack asked

"Some of them must have stuck to my clothes."

"In that case—Tosh!" Jack said into the comm. "Can you set up decontamination at the top of the stairs for when we come up? We need to make sure we don't bring any more seeds up with us."

"_I'm on it,_" she replied.

"Okay, let's get this nursery and then we can head back up and start the napalm burning."

They set fire to the napalm when they reached the stairs, trusting the combination of heat, oxygen depletion, and toxic gasses to kill the triffids without supervision. Tosh monitored the temperature to make sure the fire stayed contained and the hub wasn't at risk of exploding. Jack, Gwen, and Ianto removed their hazmat suits in a three-stage decontamination unit to make sure they didn't bring more seeds up into the hub, then Jack went to dock the triffids in the hothouse (wearing body armour this time) so that Owen could keep them for study without having to worry about getting stung. A meeting was then called to discuss the triffids.

"Despite our having dealt with the triffids in the hub," Jack started, "it's entirely possible that they either already have or will appear elsewhere. There may have been seeds escaping from the hub before Owen initiated the lockdown, and the triffids may have originated outside to begin with, so we need to be prepared to deal with them as a dangerous invasive species. Owen, have you gotten anywhere with the venom?"

"Yeah, I've had enough time to analyze it," Owen responded. "The venom has two parts to it. One is highly concentrated capsaicin, which severely irritates skin and mucous membranes that it comes in contact with. Exposure to it would basically be like taking mace and partially evaporating it so it's extra concentrated, then rubbing it all over yourself. However, that part of the venom only has any effect when that stinger doesn't break the skin, because when that happens, the other part of the venom kills you too fast for the capsaicin to do anything.

"The other component is a neurotoxin very similar to that used by box jellyfish, and causes muscle paralysis. However, because it's delivered in one huge dose and doesn't have to rely on nematocysts that might or might not fire, you get a much larger amount at once than you would from a jellyfish, leading to almost instant cardiac arrest.

"The toxin can be broken down by the body fairly quickly, but most people never get the chance to do that because they die right away. It took Jack as long as it did to recover because the toxin was still in his system until his body metabolized it. There's really no way to treat it because it acts so quickly, and I can't think of anything I can do to pre-empt it 'cause anything that stops the molecule from acting on the nerves would also affect the neurotransmitters that tell the heart when to beat. It might be possible to block the toxin's effect if someone has a pacemaker and doesn't rely on chemical signals to synchronize the heartbeat. Otherwise, blocking it would probably cause severe arrhythmia."

"If we could project electromagnetic pulses over a large area," Tosh asked, "might it be possible to treat a group of people, control their heartbeats remotely, and then have them able to safely deal with triffids?"

"Maybe," Owen considered. "Can you actually do that?"

"I'd have to test it to find a wavelength and frequency that would work for humans, but I'm pretty sure it's possible."

"Okay, Tosh, I want you working on that while you're here unless there's some other emergency," Jack said. "I can help with that if you need someone to test it on. Now, how are we going to find out about triffids outside the hub? Ideas?"

"Well," Gwen suggested, "we can have a news story put out about an invasive species, tell people to call wildlife control if they see it, and have wildlife control contact us to deal with reported triffids."

"Oh, come on, Gwen," Owen said, rolling his eyes, "seriously, how many people do you think are going to bother about an invasive species, not to mention call someone else in to deal with a weed?"

"People call lawn services to deal with nettles and things like that," she protested.

"You know," Ianto put in, "we could say that they're highly toxic, so people won't want them around, and that they can often survive being uprooted and need to be burned, so those who aren't inclined to call someone else for a weed will at least kill them effectively. We could even say they're from a genetic engineering experiment gone wrong, and they can take over crop fields. Genetically modified crops always get people up in arms and farmers won't want to risk their livelihoods."

"Great!" Jack said. "That sounds like a plan. Owen, I want you to see if herbicides have any effect on them; Ianto, you're in charge of putting out the story and producing pictures of the plants so people know what to look for; and Gwen, can you get the police and wildlife control on board with this? Tell them to burn plants that don't have flowers yet, call us for those that do. Okay, you all have your assignments, let's get going!"

With that, the members of the Torchwood team all went to work on their parts of the plan, and prepared to deal with any triffids that found their way into Wales.

And Ianto made Tosh the promised cup of Jamaican Blue Mountain coffee.


End file.
